The present invention relates to an electrical connector that meets high performance standards particularly in high speed data transmissions. More specifically, the present invention relates to an electrical connector, such as a telecommunications plug, receivable in a another mating connector, such as a telecommunications jack, that includes overtwisted wire pairs in the connector to reduce crosstalk, thereby increasing performance to meet high performance standards, such as in category 6 applications.
Advancements in telecommunications require high speed data transmission. In order to meet performance standards for high speed data transmission, such as category 6 performance standards, crosstalk must be reduced. Conventional electrical connectors, such as telecommunication plugs and jacks, produce unacceptable levels of crosstalk due to interfering signals from the wires of the connectors, thereby degrading the performance of the connector. In particular, conventional plugs, such as the industry standard RJ45 plug, terminate cables typically having eight wires that are close together and parallel leading to excessive crosstalk.
A conventional solution to this crosstalk problem is to twist each pair of wires. Specifically, when wires of a pair are twisted their equal and opposite signals cancel each other resulting in a reduction of crosstalk between the wires. However, this solution is often inadequate for high speed data transmissions, particularly due the need to untwist or separate the wires in order to connect them to pins corresponding to their terminal assignments. Specifically, the distance from where the wires are separated to the pins significantly contributes to crosstalk. Additionally, air or space between individual wires of a wire pair also affects impedance which can increases return loss or signal reflection as the signals travel through the connector, thereby decreasing performance.
Another solution to the problem of crosstalk, is to provide a dielectric insert or block where the wires are separated in the connector, thereby fixing the positions of each wire pair and reducing crosstalk by isolating the signals of the wires from each other. Although this solution reduces crosstalk, incorporation of such inserts is cost prohibitive.
Examples of conventional telecommunications electrical connectors include U.S. Pat. No. 6,007,368 to Lorenz et al; U.S. Pat. No. 5,350,324 to Guilbert; U.S. Pat. No. 5,911,594 to Baker, III et al.; U.S. Pat. No. 6,176,732 to Schultz et al.; and U.S. Pat. No. 5,226,835 to Baker, III, the subject matter of each of which is herein incorporated by reference.
Accordingly, an object of the present invention is to provide an electrical connector that reduces crosstalk and improves performance, particularly in category 6 applications.
Another object of the present invention is to provide an electrical connector that is inexpensive to manufacture and also meets performance standards for high speed data transmissions.
Yet another object of the present invention is to provide an electrical connector that includes overtwisted wire pairs to reduce crosstalk and also increase the stability of the wire pairs.
The foregoing objects are basically attained by an electrical connector including a dielectric body that has an input end and an output end opposite the input end. First and second electrical contacts are located at the output end. A twisted wire pair is connected to the first and second electrical contacts. The twisted wire pair defines an axial length includes first and second wires twisted along the axial length, and has first and second terminal ends, respectively. The first and second terminal ends are connected to the first and second electrical contacts, respectively, and include first and second portions. The first portion is located axially between the second portion and first and second terminal ends of the first and second wires. The first portion having a first degree of twist about a longitudinal axis of the twisted wire pair. The second portion has a second degree of twist about the longitudinal axis of the twisted wire pair. The first degree of twist is substantially greater than the second degree of twist.
The foregoing objects are also attained by a method of terminating wires to an electrical connector, comprising the step of twisting together first and second wires to a form a first twisted wire pair having an axial length and first and second portions,. The first portion is located axially between the second portion and the terminal ends of the first and second wires. The method also includes the step of overtwisting the first portion of the first twisted wire pair about the axial length so that the degree of twist about the axial length at the first portion is substantially greater that the degree of twist about the axial length at the second portion. Also, the method includes the step of connecting the first and second terminal ends of the first and second wires, respectively, to first and second electrical contacts, respectively, of the electrical connector.
By forming the electrical connector in the above manner, crosstalk is reduce and performance is enhanced to meet the requirements of high speed data transmissions without the use of an insert.
Other objects, advantages and salient features of the invention will become apparent from the following detailed description, which, taken in conjunction with annexed drawings, discloses a preferred embodiment of the present invention.